document paranthesis matching

others/paranthesis_matching.cpp

@@ -1,76 +1,75 @@
+/**
+ * @file
+ * @brief Perform paranthesis matching. \note Do not know the application of
+ * this, however.
+ * @note Implementation is C-type and does not utilize the C++ constructs
+ * @todo implement as a C++ class
+ */
 #include <iostream>
-#include <string>
-
-using namespace std;
+#ifdef _MSC_VER
+#include <string>  // Visual Studio C requires this include
+#else
+#include <cstring>
+#endif
 
+/** check number */
 #define MAX 100
 
-// -------------- stack --------------
-
+//! @{-------------- stack --------------
+//! global stack
 char stack[MAX];
+
+//! pointer to track stack index
 int top = -1;
 
-void push(char ch)
-{
-	stack[++top] = ch;
+//! push byte to stack variable
+void push(char ch) { stack[++top] = ch; }
+
+//! pop a byte out of stack variable
+char pop() { return stack[top--]; }
+
+//! @}-------------- end stack -----------
+
+/** return opening paranthesis corresponding to the close paranthesis
+ * @param[in] ch closed paranthesis character
+ */
+char opening(char ch) {
+    switch (ch) {
+        case '}':
+            return '{';
+        case ']':
+            return '[';
+        case ')':
+            return '(';
+        case '>':
+            return '<';
+    }
+    return '\0';
 }
 
-char pop()
-{
-	return stack[top--];
-}
-
-// -------------- end stack -----------
-
-char opening(char ch)
-{
-	switch (ch)
-	{
-	case '}':
-		return '{';
-	case ']':
-		return '[';
-	case ')':
-		return '(';
-	case '>':
-		return '<';
-	}
-}
-
-int main()
-{
-
-	string exp;
-	int valid = 1, i = 0;
-	cout << "Enter The Expression : ";
-	cin >> exp;
-
-	while (valid == 1 && i < exp.length())
-	{
-		if (exp[i] == '(' || exp[i] == '{' || exp[i] == '[' || exp[i] == '<')
-		{
-			push(exp[i]);
-		}
-		else if (top >= 0 && stack[top] == opening(exp[i]))
-		{
-			pop();
-		}
-		else
-		{
-			valid = 0;
-		}
-		i++;
-	}
-
-	// makes sure the stack is empty after processsing (above)
-	if (valid == 1 && top == -1)
-	{
-		cout << "\nCorrect Expression";
-	}
-	else
-	{
-		cout << "\nWrong Expression";
-	}
-
-	return 0;
+int main() {
+    std::string exp;
+    int valid = 1, i = 0;
+    std::cout << "Enter The Expression : ";
+    std::cin >> exp;
+
+    while (valid == 1 && i < exp.length()) {
+        if (exp[i] == '(' || exp[i] == '{' || exp[i] == '[' || exp[i] == '<') {
+            push(exp[i]);
+        } else if (top >= 0 && stack[top] == opening(exp[i])) {
+            pop();
+        } else {
+            valid = 0;
+        }
+        i++;
+    }
+
+    // makes sure the stack is empty after processsing (above)
+    if (valid == 1 && top == -1) {
+        std::cout << "\nCorrect Expression";
+    } else {
+        std::cout << "\nWrong Expression";
+    }
+
+    return 0;
 }